Items and Blocks

This section will cover all items added to the game as well as some stuff that's gotten changed.
Attack Speed: Attack Speed? With 1.9 being the Combat Update, attacking got a major overhaul. You have a speed at which you can attack, meaning spam clicking does less damage than timed hits. Haste increases Attack Speed while Mining Fatigue slows Attack Speed; to know specifics, all tools will have in their tooltip their Attack Speeds. The reason I'm including it in Items is because it affects Items and I'm not creating a separate section just to deal with the Fighting mechanics of 1.9. Sue me.
Chorus Plant: A new plant added to the game, which lives in the Outer End Islands. Breaking it is like breaking cacti, and only can be grown on Endstone. It drops the Chorus Fruit, talked about next. What are the End Islands? I'll get to that with the World Gen section coming up
Chorus Fruit: Ever want to TP around like an Enderman? Eating this plant, regardless if you're hungry or not, will TP you around just like an Enderman. The fruit heals you for 2 shanks of hunger if you are needing some food though. They have a cooldown for use though, and have another ability: cooking it in a furnace for Popped Chorus Fruit.
Popped Chorus Fruit: The result of staying in the furnace for too long, this item can't be eaten. So what good is it if you can't eat it? Well, filling a 2x2 crafting grid with this item creates a Pupur Block, which we'll talk about next!
Purpur Block and it's Variants: Purpur blocks are literally purple blocks found in the End. If you put them in the classic stair crafting pattern, you can make Purpur Stairs; put 3 in a line in the crafting grid yields a Purpur Slab; two Purpur Slabs on top of one another in the crafting grid makes Purpur Pillars. And if you think typing Purpur a lot is confusing, it is.
End Rod: A new lighting item that looks like a pull-up bar, this item is crafted similar to a torch...if you replaced the coal with a blaze rod and the stick with a Popped Chorus Fruit that is. These can be placed on any surface, and aren't affected by gravity, so sticking out of the walls and on the ceiling is perfectly fine!
End Stone Brick: We finally get a use for all that Endstone we've been hoarding! Craft these bricks by filling a 2x2 crafting grid with Endstone; they can also be found in End City dungeons. What is that? Keep reading to find out!
Grass Paths: If you ever wanted to make a halfway decent looking path from grass, now is the time! Right click grass with a shovel to turn it into a Grass Path. Note: Even when using Silk Touch, this block will drop dirt, so no mass harvesting it
Beets: when 1.9 drops, so too will Dr. DB's Beets. The beets start out as Beetroot Seeds, found in dungeon chests or very rarely Villages. Once they're all grown up, they become Beetroot, which can be crafted into Beetroot Soup, via 6 Beetroots and a bowl. Beets by themselves can heal for half a shank of hunger, while Beetroot Soup heals for 3 shanks of hunger.
Dragon's Breath: Good ol' Jean finally got a better way to hurt us in the Dragon Fight. Luckily for us, we can grab some of it up for later use. Using an empty bottle, right clicking on where the Dragon's Breath is landing will give us bottles of Dragon Breath. Useful for throwing at people? No. Useful for potions? Absolutely. Below will be all the potions added in the update.
Potions: We've got quite a few new potions out with 1.9, so I'll start with the simplest one. Water Splash Potion is just gunpowder brewed to a water bottle, and can extinguish fires when thrown. Lingering Potions are created when Dragon's Breath is brewed with a splash potion. They are used for area of effect zones that last for a little bit when thrown, but also for crafting new arrows. More on that in a bit. Potion of Luck exists, but I can't find a crafting recipe for it, or where it exists in the world...regardless, it boosts your Luck by one after you swig it.
Arrows: Big news in the arrow department. We get 15 new arrows for 1.9! The main new one is the Spectral Arrow. It's crafted like a compass...if the redstone was an arrow and the iron ingots were glowstone dust that is. It yields 2 arrows, and shows outlines to mobs and players, even if they go invisible. Awesome! The next 14 types of arrows fall under the Tipped Arrow category. They are crafted using the Lingering Potions listed above, and surrounding them with arrows. That'll give you 8 Tipped Arrows based off the Lingering potion type, and for both of these new types Infinity will use up the arrows, so plan accordingly.
Shields: The massive new addition to the Combat Update. Shields are crafted by making a Y shape in the crafting table, and filling the top middle slot with an iron ingot. They reduce some, but not all damage, and can be "disabled" for 5 seconds if hit with an axe. If you have a banner, you can add this to your shield by simply putting it next to your shield in the crafting grid.
Boats: Boats got fixed! There's also some variants to it, depending on the planks you use to craft it. Boats are made the same way as before, but the wood types will determine the color of your boat; it also can hold 2 entities and has paddles!
Enchanted Golden Apples AKA Notch Apples: These OP suckers can only be found in chests now, as their golden block crafting recipe is getting removed. You can still craft the normal Golden Apples, using an apple surrounded by Gold Ingots.
Shears and Swords: Shears can't be used with Silk Touch anymore, and slowly lose durability when it breaks any block. You also get cobwebs when you break them with Shears now. Blocking also got removed from Swords, because Shields were made now. The "Sweep Attack" replaced it, knocking mobs/players back if it hits, and yes, that is affected by knockback
End Crystal: That floating crystal of explosiveness can be crafted now! Place an Eye of Ender in the middle of the crafting grid, place a Ghast Tear below that in the bottom center, and fill the rest with glass blocks for a brand new End Crystal. Warning: can only be placed on Obsidian or Bedrock, and used for respawning the Ender Dragon.
Elytra: The thing that's making 1.9 totally worth it. These "wings" go on your chestplate slot, and are activated when pressing SPACE in mid-air. The gliding works for up to 7 minutes, and can be repaired with leather. Where would you find such an amazing item? In an End Ship. More on that soon

Mobs

This covers all the major Mob changes in 1.9, as well as adding a brand new mob!
Shulker: As close to turtles as we've got in MC so far, these guys hang out in End Cities. They throw out projectiles that give you, if hit, a heart of damage included with the Levitation effect. They look like blocks, so be careful when exploring the cities!
Left Handed Mobs: With the new hand mechanics, explained shortly, mobs can now spawn with items in their dominant hands, or in their offhand. Lefties unite!
Ender Dragon: 1.9 could have also been called the End Update, as the End got a massive re-work. Starting with the Ender Dragon and the fight. Not only does the dragon breathe "fire" now, cages are around the End Crystals, making the fight much harder. On top of that, killing the dragon generates an End Gateway, which will be mentioned soon. The Egg still spawns on top of the Exit Portal, BUT destorying it still means it's gone forever. However, using End Crystals, you can bring the Ender Dragon back to generate up to 20 End Gateways. To do so, you place an End Crystal on each of the main sides of the Exit Portal, and watch the magic happen
Rabbits: Throwing this stuff in here cause it's cool and I didn't know about these changes. Rabbit health dropped to a heart and a half, and they're smaller than before. They also have a a 25% less chance at dropping the Rabbit's Foot when killed, and the biome they spawn in affects the skin type they have.

Overall Gameplay

This section is going over the main changes that are taking place to the players in 1.9
Dual Wielding: Yep, we got it. You can now use your previously non-existent left hand in the game! Pressing F selects whatever item you're holding in your dominant hand to switch to your left side. It looks like a shield in your Inventory when you pull it up. Main hand can still be only used for physical attacks, so no dual wielding OP diamond swords
Status Effects: We've got 4 new Effects that can happen to players with 1.9. Glowing happens when a player or mob has been hit by a Spectral Arrow. Levitation happens when hit by a Shulker projectile, and yes, Levitation can kill you. Luck and Bad Luck both exist by raising or lowering your Luck level by 1. How you get them, not a clue.
Enchantments: "Treasure" enchantments exist now, which can only be obtained from chests, trading with villagers, or fishing. The two new ones are Frost Walker and Mending. Frost Walker is for boots only, and lets you walk over water, freezing it below your feet. Don't worry about oceans getting covered with ice though - the ice decays once the sun comes up. This also can't be combined with Depth Strider. Mending uses your XP to repair items. Each XP number will "heal"/repair your gear for offhand, armor slots, and main hand. Useful for the Elytra, and picks while mining.

World Generation Changes

Here's where we talk about all the new additions into the World of Minecraft, including some minor changes to existing things!
The End: Holy mother of Notch, this has been a long time coming. The End got the biggest overhaul for this update out of all the places in the world. Once you kill the Ender Dragon, an End Gateway appears. Throwing an Ender Pearl through it will teleport you out to the Outer End Islands. The Outer End Islands can have many options; some can have Chorus Tree forests, some can have End Cities, some can be barren expanses. End Cities hold Shulkers and rare loot chests, along with End Ships. End Ships house not only rare loot, it also contains Dragon Heads on the front, and Elytras in the cabin. These items can only be found in End Ships, so be careful and search well!
Igloos: These small frozen homes can be found in Ice Plains or Cold Taigas, sometimes housing Zombie Villagers under them. If it does, it provides you with the materials to cure the Zombie Villager right there, so be on the lookout for them!
Strongholds: The number of these got upped from 3 to 128, making them much more "easier" to find. And by find, I mean just as hard. No strongholds will spawn past 24,200 blocks from the center of the world, so you've got plenty of space to go and raid them for bookshelves and rare materials. Also, there's a 0.0000000001% chance that all 12 frame blocks generate with eyes already present, which means active End Portal. May the odds be in your favor

Extra Notes

I'm throwing this section together from just some random facts about the update, along with some extra added things!
Command blocks now have "Repeat" and "Chain" variants for faster and simpler command block structures!
Skeleton Horses can sometimes spawn now!
385 bug fixes happened for 1.9
1.9 has had 56 snapshots for it, the most for any release, as well as the longest period of time between releases, at 534 days, with a 330 day gap between when 1.8 was released and the first 1.9 snapshot occurring.
Turtles still don't exist in Minecraft
Hay bales reduce damage just like Assassins Creed; only difference is it can still kill you - no armor kills you from anything above 100 blocks, and feather falling can keep you alive up to 169 blocks
Loads of commands and performance updates! No more Twitch integration and Super Secret Settings is also gone! Your worlds now show you what the last version it was you played it on! Thumbnails for your worlds exist now!